According to a tweet from @FlightAlerts_, an account which tracks aircraft emergencies around the world, the Boeing 787-8 Dreamliner had to make a diversion to the Austrian capital due to an “oil leak in the left engine”.

However, the airline did not confirm reports of an engine leak, saying it is still investigating the matter:

“RB is aware of the news currently circulated on a reported oil leak. We are currently conducting a thorough investigation to identify the nature of the incident,” read an official statement from the airline.

“The safety and security of our guests is of paramount importance to RB and all guests have been rerouted on other carriers.”

Photographs shared on social media also showed fire and rescue personnel inspecting the left engine of the Boeing aircraft.